/*****************************************************************************
 * Copyright (c) 2012 CEA LIST.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *  Camille Letavernier (CEA LIST) camille.letavernier@cea.fr - Initial API and implementation
 *****************************************************************************/
package org.eclipse.papyrus.infra.gmfdiag.css.cdo;

import org.eclipse.emf.common.notify.Notification;
import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.EStructuralFeature;
import org.eclipse.emf.ecore.impl.ENotificationImpl;
import org.eclipse.gmf.runtime.notation.ArrowType;
import org.eclipse.gmf.runtime.notation.NotationPackage;
import org.eclipse.gmf.runtime.notation.View;
import org.eclipse.emf.cdo.gmf.notation.impl.ArrowStyleImpl;
import org.eclipse.papyrus.infra.gmfdiag.css.engine.ExtendedCSSEngine;
import org.eclipse.papyrus.infra.gmfdiag.css.notation.CSSDiagram;
import org.eclipse.papyrus.infra.gmfdiag.css.notation.ForceValueHelper;
import org.eclipse.papyrus.infra.gmfdiag.css.style.CSSArrowStyle;
import org.eclipse.papyrus.infra.gmfdiag.css.style.impl.CSSArrowStyleDelegate;

public class CSSArrowStyleImpl extends ArrowStyleImpl implements CSSArrowStyle {

	protected ExtendedCSSEngine engine;

	private CSSArrowStyle arrowStyle;

	protected CSSArrowStyle getArrowStyle() {
		if (arrowStyle == null) {
			arrowStyle = new CSSArrowStyleDelegate(this, getEngine());
		}
		return arrowStyle;
	}

	protected ExtendedCSSEngine getEngine() {
		if (engine == null) {
			engine = ((CSSDiagram) findView().getDiagram()).getEngine();
		}
		return engine;
	}

	protected View findView() {
		EObject parent = eContainer();
		while (!(parent instanceof View) && parent != null) {
			parent = parent.eContainer();
		}

		if (parent != null) {
			return (View) parent;
		}

		return null;
	}


	// ////////////////////////////////////////
	// Forwards accesses to CSS properties //
	// ////////////////////////////////////////


	@Override
	public ArrowType getCSSArrowSource() {
		ArrowType value = super.getArrowSource();

		if (ForceValueHelper.isSet(findView(), this, NotationPackage.eINSTANCE.getArrowStyle_ArrowSource(), value)) {
			return value;
		} else {
			return getArrowStyle().getCSSArrowSource();
		}
	}

	@Override
	public ArrowType getCSSArrowTarget() {
		ArrowType value = super.getArrowTarget();

		if (ForceValueHelper.isSet(findView(), this, NotationPackage.eINSTANCE.getArrowStyle_ArrowTarget(), value)) {
			return value;
		} else {
			return getArrowStyle().getCSSArrowTarget();
		}
	}


	@Override
	public ArrowType getArrowSource() {
		return getCSSArrowSource();
	}

	@Override
	public ArrowType getArrowTarget() {
		return getCSSArrowTarget();
	}


	// //////////////////////////////////////////////
	// Implements a setter for each CSS property //
	// //////////////////////////////////////////////

	@Override
	public void setArrowSource(ArrowType value) {
		ArrowType oldArrowSource = getArrowSource();

		boolean deliver = eDeliver();
		try {
			// Do not rely on super implementation for sending the event. Just change the value.
			eSetDeliver(false);
			super.setArrowSource(value);
		} finally {
			eSetDeliver(deliver);
		}

		EStructuralFeature feature = NotationPackage.eINSTANCE.getArrowStyle_ArrowSource();
		ForceValueHelper.setValue(findView(), feature, value);

		// Bug YYY YYY: Super implementation doesn't rely on "getArrowSource" and doesn't properly compute oldArrowSource
		if (eNotificationRequired()) {
			eNotify(new ENotificationImpl(this, Notification.SET, NotationPackage.ARROW_STYLE__ARROW_SOURCE, oldArrowSource, value));
		}
	}

	@Override
	public void setArrowTarget(ArrowType value) {
		super.setArrowTarget(value);

		EStructuralFeature feature = NotationPackage.eINSTANCE.getArrowStyle_ArrowTarget();
		ForceValueHelper.setValue(findView(), feature, value);
	}

	// ////////////////////////////////
	// Implements the unset method //
	// ////////////////////////////////

	@Override
	public void eUnset(int featureId) {
		super.eUnset(featureId);

		EStructuralFeature feature = eClass().getEStructuralFeature(featureId);
		ForceValueHelper.unsetValue(findView(), feature);
	}


}